The present invention relates generally to an apparatus and method for purifying, carbonating and dispensing a liquid from tap. This invention relates more particularly to an apparatus and method for obtaining a liquid, such as water from a source, purifying the liquid, supplying a carbonating gas, such as CO.sub.2, to the pre-purified liquid and dispensing either a carbonated and purified supply of water or purified water only from a tap.
Carbonated beverages have been quite popular for a considerable period of time. For many years seltzer water or soda water, consisting of purified carbonated water with or without salt, have been the drink of choice of millions of people worldwide. To date, however, those desiring to drink carbonated water either purchased bottled carbonated water at the store, purchased it from a fountain or made carbonated water in a small bottle, usually one or two liters in size, by using a CO.sub.2 cartridge to charge tap water with carbonation. Despite the wide spread popularity of drinking carbonated water, there is no apparatus or method of making carbonated water available in the home, workplace or commercial area which taps into the plumbing, filters the water and charges the purified water with carbonation for dispensing at a faucet.
Presently a number of different apparatus exist for carbonating a liquid and a number of different apparatus exist for purifying a liquid. However, no single apparatus exists which purifies and carbonates a liquid obtained from a building's water source. Each of the conventional carbonation apparatus are characterized by having a carbonation chamber which, generally, consists of a reservoir for holding the fluid to be charged with the carbonating gas and a gas inlet for introducing the carbonating gas directly into the fluid contained in the reservoir. Typically, each of the carbonation chamber containers have at least three ports associated with the container. A first port is a fluid inlet port for introducing the fluid to be charged with the carbonating gas into the container. A second port is the gas inlet port for introducing the carbonating gas into the fluid contained within the container. The third port is a fluid outlet port for evacuating the carbonated fluid from the container. Examples of presently existing apparatus for carbonating and dispensing a liquid are show in U.S. Pat. No. 4,497,348 issued Feb. 5, 1985 to Jason Sedam and entitled "APPARATUS AND METHOD FOR LOADING SYRUP AND CO.sub.2 CONTAINERS INTO A PORTABLE POST-MIX BEVERAGE DISPENSER UNIT;" U.S. Pat. No. 4,509,569 issued Apr. 9, 1985 to Bengt O. Adolfsson and entitled "ARRANGEMENT FOR SUPPLYING GAS TO A LIQUID IN A CONTAINER THEREFORE;" U.S. Pat. No. 4,514,994 issued May 7, 1985 to Kenneth G. Mabb and entitled "APPARATUS FOR AERATING LIQUIDS;" U.S. Pat. No. 4,564,126 issued Jan. 14, 1986 to Bengt O. Adolfsson and entitled "ARRANGEMENT FOR SUPPLYING GAS TO A LIQUID IN A CONTAINER THEREFORE;" U.S. Pat. No. 4,597,509 issued July 1, 1986 to LeRoy A. Pereira and entitled "DRINKING WATER DISPENSING UNIT AND METHOD;" and U.S. Pat. No. 4,708,827 issued Nov. 24, 1987 to John R. McMillin and entitled "METHOD OF AND APPARATUS FOR MAKING AND DISPENSING CARBONATED WATER WITH A DOUBLE DIAPHRAGM PNEUMATIC WATER PUMP."
In each of these examples of conventional carbonation units the carbonating gas is introduced directly into the fluid contained within the carbonation chamber. It is to be noted that in each of these conventional apparatus, the fluid to be charged with the carbonating gas is introduced into the carbonating chamber prior to introduction of the carbonating gas. The carbonating gas is, therefore, charged into a stagnant reservoir of the fluid. The resulting gas-fluid intermixing within the carbonating chamber provides unsatisfactory gas loading in the fluid. Thus, upon dispensing of the carbonated beverage, the carbonated state of the fluid is more transient due to the lower level of gas saturation in the fluid. This typically provides unsatisfactory commercial results and consumer response to the product.
U.S. Pat. Nos. 4,497,348, 4,509,569 and 4,564,126 disclose carbonating apparatus which charge a reservoir of unchilled fluid with a carbonating gas. However, in each case the apparatus relies upon pressurization within the carbonation chamber to maintain the gas-saturation level within the fluid. Upon evacuation of the charged fluid from the carbonation chamber, however, the carbonated fluid is exposed to an immediate decrease in ambient pressure which results in rapid depletion of the carbonation level in the fluid.
As recognized in U.S. Pat. No. 4,514,994, it is well known that carbonation loading of water is improved if the water is chilled prior to charging with the carbon dioxide gas. As further recognized in that patent, it is usual to include, in the known carbonating plants, a cooler for cooling the water before carbonation, or to provide refrigerated water prior to introducing the carbonating gas. Because the use of cooled water facilitates carbonation, refrigeration units or other means for chilling the water prior to carbonation are important components of U.S. Pat. Nos. 4,597,509, 4,514,994 and 4,708,827.
Heretofore, however, satisfactory carbonation has been difficult to achieve without use of refrigeration units. Thus, a need has existed for an apparatus which produces carbonated liquid from an unchilled liquid source. An important aspect of the present invention is to provide an apparatus and method for producing carbonated water employing the existing building plumbing as a water source and a carbonation unit employing a carbonation diffuser for mixing the carbonating gas and water and discharging a finely charged flow of carbonated water.
A second important aspect of the present invention is to provide a filtration unit interdisposed between the water source and the carbonation unit. The filtration unit acts to prefilter the water conducted from the water source prior to introducing the purified water into the carbonation chamber. There are, of course, numerous and diverse types of water filters. Examples of such conventional water filters may be found in U.S. Pat. No. 3,535,235 issued Oct. 20, 1970 to A. C. Schouw and entitled "FILTER APPARATUS;" U.S. Pat. No. 3,950,253 issued Apr. 13, 1976 to Emanuel Stern and entitled "DOMESTIC WATER FILTRATION APPARATUS;" U.S. Pat. No. 3,963,620 issued June 15, 1976 to Zdenek Vor and entitled "PURIFICATION FILTER FOR LIQUIDS;" U.S. Pat. No. 4,049,550 issued Sept. 20, 1977 to Louis Obidniak and entitled "WATER FILTRATION MODULE;" U.S. Pat. No. 4,312,754 issued Jan. 26, 1982 to Pierre LaFonaine and entitled "PORTABLE WATER PURIFIER ESPECIALLY FOR DOMESTIC USE;" and U.S. Pat. No. 4,609,466 issued Sept. 2, 1986 to Calvin W. McCausland et al and entitled "PORTABLE WATER PURIFICATION SYSTEM." In each of the foregoing patents there is disclosed an in-line water filter apparatus which is interdisposed between a water source and an outlet port through which purified water is withdrawn from the circuit.
None of the foregoing patents disclose an apparatus for purifying, carbonating and dispensing both purified and purified uncarbonated water and purified carbonated water from a tap. A need has been recognized, therefore, to provide a simple apparatus capable of dispensing both purified uncarbonated water and purified carbonated water from tap.